Cardiovascular disease is counted among the most common diseases in Western countries and its occurrence is increasing also in Asian countries. The most important individual risk factor is elevated serum LDL cholesterol level, and therefore, lowering of the serum concentrations of LDL cholesterol is the most effective single measure regarding both prevention and effective treatment of cardiovascular disease.
The most important drugs for reduction of serum cholesterol levels are the statins, which function primarily by inhibiting the synthesis of cholesterol, mainly in the liver. The most common side effects of the statins are gastrointestinal. Other less common side effects include headache, dizziness, rash, and sleep disturbances. In addition, statins may cause both liver damage and muscle disorders, and they have been reported to increase the risk of type II diabetes.
As an alternative to cholesterol lowering drugs, or in addition to them, also life style changes can reduce the risk of cardiovascular diseases. In particular increasing physical exercise and/or adopting healthy diets recommended by governments or non-governmental associations are beneficial. An additional nutritional way to reduce serum LDL cholesterol levels is the use of cholesterol lowering functional foods that can be consumed as part of any conventional diet. This alternative has been greatly welcomed by consumers.
Food products enriched with components having a cholesterol lowering effect have been commercially available for almost 20 years. Such functional food products usually contain plant sterols and/or plant stanols and especially their fatty acid esters as active ingredients. Plant sterols have since the early 1950's been known to reduce serum cholesterol levels. U.S. Pat. No. 6,174,560 describes plant stanol fatty acid esters, a method for their preparation, and the cholesterol lowering effects thereof. An intake of 2 g per day of plant stanols is reported to lower serum LDL cholesterol levels in man up to 14%. Benecol is a well-known trademark for plant stanol ester containing products and nowadays plant stanol ester is used in a variety of food products. Many of these products, e.g. margarine-type spreads and drinkable and spoonable yoghurts, need continuous refrigeration. However, many consumers would prefer to have their daily dose of plant sterols and/or plant stanols available in a product that can be carried along wherever they go, e.g. as a dietary supplement.
One of the most common type of dietary supplements are capsules, such as soft gelatin capsules, so called softgel capsules. Capsules consist of a shell and a filling containing the active ingredient.
Softgel capsules containing plant sterol ester and/or plant stanol ester have already been disclosed. The clinical trials conducted with these softgel capsules have yielded variable results. Most clinical studies with plant sterol ester and/or plant stanol ester softgel capsules have failed to deliver the expected serum LDL cholesterol lowering efficacy compared with the corresponding clinical trials with plant sterol ester and/or plant stanol ester functional food products. In a recent study of Ottestad et al. (Atherosclerosis 2013 June; 228(2):421-5) a softgel capsule containing plant sterol ester (2 g/d plant sterols) did not lower serum LDL cholesterol in hypercholesterolemic subjects. The authors concluded that this delivery system (softgel capsules) of plant sterol ester does not seem to give the expected LDL cholesterol reduction and thus the clinical relevance of the consumption of plant sterol ester capsules remains uncertain.
The softgel capsules that have been commercially available or are currently on the market contain plant sterol ester and/or plant stanol ester as such or mixed with vegetable oil, e.g. 80% plant sterol ester and/or plant stanol ester and 20% vegetable oil. Usually the recommended daily amount of plant sterols and/or plant stanols is 2 g, which means that the daily minimum required amount of plant sterol ester and/or plant stanol ester is about 3.4 g. Therefore the size of capsules is big, delivering about 1 g plant sterol ester and/or plant stanol ester in each soft gelatin capsule. For optimal cholesterol lowering efficacy plant sterol ester and/or plant stanol ester capsules are recommended to be consumed with a meal.
Because the clinical relevance of plant sterol ester and/or plant stanol ester capsules has been questioned, there remains a need for improved plant sterol ester and/or plant stanol ester capsules that will deliver the expected serum LDL cholesterol lowering effect when consumed as recommended.